Ultra-broadband Mid to Long-wave Infrared Spintronic Poisson Bolometer

TL;DR

This paper introduces a novel spintronic Poisson bolometer capable of ultra-broadband infrared detection from 3 to 14 micrometers at room temperature, using stochastic event counting to improve sensitivity and integrate mid- and long-wave IR sensing.

Contribution

The work presents the first implementation of a spintronic Poisson bolometer with broadband IR detection and stochastic counting, enabling room-temperature operation and surpassing traditional uncooled detectors.

Findings

Achieved NETD of 80-100 mK at 300 K.

Demonstrated broadband detection from 3 to 14 micrometers.

Implemented stochastic event counting for IR sensing.

Abstract

Infrared detectors have traditionally been divided into two fundamental classes, mid-wave (MWIR, 3-5 um) and long-wave (LWIR, 8-14 um). Integrating MWIR and LWIR within a single device is challenging due to distinct materials, cooling needs, and detection mechanisms, while such integration is critical for improved object recognition, temperature estimation, and environmental sensing. In this work, we demonstrate a Spintronic Poisson (SP) bolometer enabling room-temperature ultra-broadband sensing across 3-14 um. Unlike conventional bolometers that rely on continuous analog signals, the SP bolometer implements a Poisson-counting detection paradigm, encoding temperature in discrete stochastic events, which turns thermal noise from a limitation into the basis of the estimator itself. We fabricate the SP bolometer using a spintronic transduction layer integrated with a plasmonic nanoantenna array to enhance broadband infrared absorption. Using spintronic transduction, the device achieves the noise-equivalent temperature difference (NETD, thermal sensitivity metric) of 80-100 mK at 300 K, surpassing uncooled detectors and approaching cooled technologies. This work establishes a statistical detection paradigm for room-temperature infrared sensing with broad application potential.